Medical cleaning valve

ABSTRACT

A medical valve may comprise a valve stem and an operation portion. The operation portion may include a stationary portion, a movable portion which is movable relative to the stationary portion and fixed relative to the valve stem, a seal disposed between the stationary portion and the movable portion, and a biasing member. Movement of the movable portion in a first direction may cause deformation of the biasing member, such that a restorative force of the biasing member urges movement of the movable portion in a second direction opposite the first direction. A frictional force between the seal and one of the stationary portion and the movable portion resists the movement of the movable portion in the second direction.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority from U.S. ProvisionalApplication No. 62/862,893, filed on Jun. 18, 2019, which isincorporated by reference herein in its entirety.

TECHNICAL FIELD

The present disclosure relates generally to valves for medical devices,particularly endoscopes.

BACKGROUND

Endoscopes include functionality to deliver fluids (including air andwater) and suction to a site of a procedure. Tubing for deliveringfluids and/or suction extends from a handle of the endoscope, through asheath of the endoscope, and to a distal tip of the endoscope. During aprocedure, body fluids, tissues, or other material can build up in thetubing and, in some cases, lead to clogging of the tubing. In order toaid in reprocessing of reusable endoscopes between procedures,pre-processing is performed in an endoscopy suite. For example, water orother fluids are flushed through the tubing after the endoscope isremoved from a patient, in order to clear debris from the air/waterand/or suction tubing. One option for accomplishing such pre-processingis a reusable cleaning valve. The cleaning valve may be inserted into anair/water valve cylinder of an endoscope after the scope is removed froma patient. An operator may then depress a button of the cleaning valvefor a predetermined amount of time (e.g., 30 seconds) to flush the airand/or water channels of the endoscope prior to further reprocessing ofthe endoscope. Such cleaning may require active intervention by anoperator. A reusable cleaning valve must be subject to cleaning, itself,in between uses, which can add to reprocessing cost. Therefore, a needexists for valves capable of performing cleaning functions.

SUMMARY

In one example, a medical valve may comprise a valve stem and anoperation portion. The operation portion may include a stationaryportion and a movable portion. The movable portion may be movablerelative to the stationary portion and fixed relative to the valve stem.A seal may be disposed between the stationary portion and the movableportion. The operation portion may further include a biasing member.Movement of the movable portion in a first direction may causedeformation of the biasing member, such that a restorative force of thebiasing member urges movement of the movable portion in a seconddirection opposite the first direction. A frictional force between theseal and one of the stationary portion and the movable portion resiststhe movement of the movable portion in the second direction.

Any of the medical valves disclosed herein may include any of thefollowing features. The biasing member may be a spring. The movableportion may be movable in the first direction from a first configurationto a second configuration. A relationship between the frictional forceand the restorative force may be such that, after the movable portion istransitioned from the first configuration to the second configuration,the movable portion will automatically move in the second direction toreturn to the first configuration. A radially outer surface of the valvestem may include a first aperture and a second aperture. The valve stemmay include a lumen extending along a longitudinal axis of the valve.The lumen may be in fluid communication with the first aperture and thesecond aperture. A proximal seal, a one-way seal, and three distal sealsmay be disposed on an outer surface of the valve stem. The firstaperture may be between the proximal seal and the one-way seal. Thesecond aperture may be between a first of the three distal seals and asecond of the three distal seals. The valve may be movable in a proximaldirection and a distal direction relative to a valve cylinder thatreceives the valve. The valve may be rotatable about a longitudinal axisof the valve and relative to a valve cylinder that receives the valve. Afirst and a second rotatable seal may be disposed on the valve stem. Ina first configuration of the valve, a first hole in the first rotatableseal and a second hole in the second rotatable seal may face a firstdirection. In a second configuration of the valve, the first hole andthe second hole may face a second direction different from the firstdirection. The valve may also include an O-ring seal between the firstrotatable seal and the second rotatable seal. The first hole may bealigned with a first aperture in a radially outer surface of the valvestem. The second hole may be aligned with a second aperture in theradially outer surface of the valve stem. Each of the first and secondrotatable seals may include a recessed notch extending partially aroundan outer circumference of the rotatable seal. The first hole may bewithin the recessed notch of the first seal. The second hole may bewithin the recessed notch of the second seal. The movable portion mayinclude a rim that extends between inner and outer cylindrical portionsof the stationary portion. The stationary portion may include a matingfeature for mating with a valve cylinder of an endoscope. The valve stemmay be a single, unitary structure formed of a single material.

In another example, a medical valve may comprise a movable portionmovable between a first configuration and a second configuration; astationary portion, a seal disposed between the stationary portion andthe movable portion and providing a frictional force between thestationary portion and the movable portion; and a spring. Transitioningthe movable portion from the first configuration to the secondconfiguration may deform the spring. The deformed spring may exert arestorative force urging the movable portion back to the firstconfiguration. A relationship between the frictional force and therestorative force may be such that, after the movable portion istransitioned from the first configuration to the second configuration,the movable portion will automatically return to the first configurationafter an amount of time.

Any of the medical valves disclosed herein may include any of thefollowing features. The valve may be movable in a proximal direction anda distal direction relative to a valve cylinder that receives the valve.The valve may be rotatable about a longitudinal axis of the valve andrelative to a valve cylinder that receives the valve.

A method for cleaning an endoscope may comprise providing a force to avalve to transition the valve from a first configuration in which wateris not delivered to an air channel to a second configuration in whichwater is delivered to an air channel; and releasing the force. After theforce is released, the valve may continue to deliver water to the airchannel for an amount of time before automatically transitioning back tothe first configuration.

Any of the methods disclosed herein may include the following steps oraspects. The valve may include a movable portion; a stationary portion;a seal disposed between the stationary portion and the movable portionand providing a frictional force between the stationary portion and themovable portion; and a spring. Transitioning the movable portion fromthe first configuration to the second configuration may deform thespring. The deformed spring may exert a restorative force urging themovable portion back to the first configuration. A relationship betweenthe frictional force and the restorative force may be such that, afterthe movable portion is transitioned from the first configuration to thesecond configuration, the movable portion will automatically return tothe first configuration after the amount of time.

It may be understood that both the foregoing general description and thefollowing detailed description are exemplary and explanatory only andare not restrictive of the invention, as claimed. As used herein, theterms “comprises,” “comprising,” or any other variation thereof, areintended to cover a non-exclusive inclusion, such that a process,method, article, or apparatus that comprises a list of elements does notinclude only those elements, but may include other elements notexpressly listed or inherent to such process, method, article, orapparatus. The term “exemplary” is used in the sense of “example,”rather than “ideal.” As used herein, the term “proximal” means adirection closer to a surface used by an operator for operating a valve(e.g., a button) and the term “distal” means a direction away from thesurface used by an operator for operating a valve (e.g., a button).Although endoscopes are referenced herein, reference to endoscopes orendoscopy should not be construed as limiting the possible applicationsof the disclosed aspects. For example, the disclosed aspects may be usedwith duodenoscopes, bronchoscopes, ureteroscopes, colonoscopes,catheters, diagnostic or therapeutic tools or devices, or other types ofmedical devices.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate examples of the presentdisclosure and, together with the description, serve to explain theprinciples of the disclosure.

FIGS. 1A and 1B show cross-sectional views of a first exemplary valve.

FIGS. 2A and 2B show cross-sectional views of a second exemplary valve.

FIGS. 3A-3D show exemplary seals that may be used in conjunction withthe second exemplary valve of FIGS. 2A and 2B.

DETAILED DESCRIPTION

A valve may be configured to provide cleaning functionality to an airchannel of an endoscope. In at least some embodiments, the valve may beappropriate for a single-use and therefore be disposable. In a firstconfiguration, the valve may provide neither air nor water flow to airand/or water channels of an endoscope. In a second configuration, thevalve may provide only water flow to only an air channel of theendoscope. The valve may include features that, after the valve istransitioned from the first configuration to the second configuration,retain the valve in the second configuration for a predetermined amountof time, such as a time specified for flushing an air valve in acleaning protocol. Thus, the valve may be in a second, flushingconfiguration for a predetermined amount of time without activeparticipation by a user, so that the user may perform other tasks duringthe flushing of the air channel of the endoscope. After thepredetermined amount of time, the valve may transition from the secondconfiguration back to the first configuration automatically.

FIGS. 1A-1B show cross-sectional views of a first exemplary cleaningvalve 10 in a valve cylinder 39. FIG. 1A shows valve 10 in a firstconfiguration, and FIG. 1B shows valve 10 in a second configuration.Valve cylinder 39 may have a water inlet A, a water outlet B, an airinlet C, and an air outlet D. Water inlet A may be in fluidcommunication with a source of water or other liquid (e.g., water,cleaning solution, air, other gases, or combinations thereof). Wateroutlet B may be in fluid communication with a water channel of anendoscope (not shown), which may extend from a proximal end of theendoscope to a distal end of the endoscope. During a medical procedure,the water channel may be used to deliver water at a site of theprocedure. Air inlet C may be in fluid communication with a source ofair or other fluid (e.g., air, other gases, water, or cleaning solution,or combinations thereof). Air outlet D may be in fluid communicationwith an air channel of the endoscope. During a medical procedure, theair channel may be used to deliver air at a site of the procedure.

Valve 10 may have a proximal end 12 and a distal end 14. A valve stem 16may extend from proximal end 12 to distal end 14. A cap 18 (which may bean operation portion of valve 10) may be disposed at proximal end 12.Valve stem 16 may be a single, unitary structure formed of a single,continuous piece of material and may be made from a metal (e.g.,stainless steel, titanium, aluminum, etc.), from a polymer (e.g.polycarbonate, ABS, HDPE, Nylon, PEEK, thermoplastic, plastic, etc.), orfrom any other suitable material. Depending on the material used, valvestem 16 may be machined, injection molded, extruded (via, e.g., 3Dprinting), or otherwise formed. Valve stem 16 may be formed of a clearthermoplastic so that certain portions of an interior of valve stem 16are visible through external walls of inner cylindrical member.

Valve stem 16 may have a lumen 22 extending through a centrallongitudinal axis of valve stem 16. Alternatively, lumen 22 may extendthrough another longitudinal axis of valve stem 16 (e.g., lumen 22 maybe off-centered). A space between an exterior surface of valve stem 16and a surface defining lumen 22 may be solid, and lumen 22 may be a boreformed in valve stem 16. In another example, a space between an exteriorsurface of valve stem 16 and a surface defining lumen 22 may be hollow.In such a case, lumen 22 may be formed by a longitudinal tube withinvalve stem 16.

Lumen 22 may be open to an exterior of valve stem 16 on a proximal endof lumen 22 via one or more proximal apertures 24. For example, lumen 22may be fluidly connected to proximal aperture(s) 24 via a second,proximal lumen (not shown) which may be transverse to lumen 22. Forexample, the second lumen may be perpendicular to lumen 22 (extendinginto the page in FIG. 1A). Lumen 22 may be open to an area exterior ofvalve stem 16 on a distal end of lumen 22 via one or more distalapertures 26. Lumen 22 may be fluidly connected to distal aperture(s) 26via a third, distal lumen (not shown) which may be transverse to lumen22. For example, the third, distal lumen may be perpendicular to lumen22 (extending into the page in FIG. 1A).

Valve stem 16 may have disposed on it a first distal seal 32, a seconddistal seal 34, and a third distal seal 36. Distal seals 32, 34, 36 maybe made from elastomeric material. Distal seals 32, 34, 36 may beidentical to one another and may be, for example, O-rings. Distal seals32, 34, 36 may be disposed in circumferential, annular grooves orindentations on valve stem 16. A durometer value and outer diameter ofdistal seals 32, 34, 36 may be such that the distal seals 32, 34, 36have an interference fit with an inner surface 38 of an endoscope valvecylinder 39 when valve 10 is inserted in endoscope valve cylinder 39.The interference fit may be loose enough so that valve stem 16 mayslidably move relative to surface 38 but tight enough so that fluidscannot flow longitudinally between a radially outermost surface of seals32, 34, 36 and surface 38. Third distal seal 36 may be disposed near toa distal end 14 of valve 10, distal to distal aperture 26. Second distalseal 34 may be proximal of third distal seal 36 and proximal to distalaperture 26. First distal seal 32 may be proximal of second distal seal34 but still distal of proximal aperture 24.

Valve stem 16 may also have disposed on it a proximal seal 42. Proximalseal 42 may have any of the properties of distal seals 32, 34, 36. Forexample, proximal seal 42 may be an elastomeric O-ring and may bedisposed in an annular circumferential groove or indentation of valvestem 16. A durometer value and outer diameter of proximal seal 42 may besuch that the proximal seal 42 has an interference fit with surface 38(see FIGS. 1A-1B) when valve 10 is inserted in endoscope valve cylinder39. The interference fit may be loose enough so that valve stem 16 mayslidably move relative to endoscope valve cylinder surface 39 but tightenough so that fluids cannot flow longitudinally between a radiallyoutermost surface of proximal seal 42 and surface 38. Proximal seal 42may have a larger inner diameter than distal seals 32, 34, 36 due to asmall diameter of the groove within valve stem 16 at a location ofproximal seal 42. Proximal seal 42 may have a larger outer diameter thandistal seals 32, 34, 36 due to a wider space defined by surface 38 atthe location of seal 42 compared to a space defined by surface 38 at thelocation of seals 32, 34, 36. It is understood that seals 32, 34, 36,and 42 may be any size to fit around the valve stem 16 and to sealagainst surface 38 to selectively prevent fluid flow.

Valve stem 16 may also be fitted with a one-way seal 62, which may bedisposed longitudinally along the valve stem 16 between first distalseal 32 and proximal seal 42. One-way seal 62 may be formed of anelastomeric material, which may stretch to fit over valve stem 16.One-way seal 62 may be disposed in a groove or indentation of valve stem16. An inner surface of one-way seal 62 may be sized so that there is aslight interference between an external surface of valve stem 16 and theinner surface of one-way seal 62, so that a tight seal is formed. Anouter diameter of one-way seal 62 may be sized so as to form a slightinterference fit with surface 38 (see FIGS. 1A-1B). A thin flap ofone-way seal 62 may extend radially outward from valve stem 16 at anangle transverse to a longitudinal axis of valve stem 16. For example,the thin flap may extend at an angle between approximately 10 degreesand 80 degrees relative to a longitudinal axis of valve stem 16. Theflap of one-way seal 62 may be expandable so that when fluid (e.g.,water or air) moves in a distal direction, a positive pressure willexpand the flap, maintaining a seal between one-way seal 62 and surface38 (see FIGS. 1A-1B). Fluid moving proximally will also create apositive pressure, but the positive pressure will produce a force normalto a longitudinal axis of valve stem 16 to radially compress the flap ofone-way seal 62 toward valve stem 16. Thus, fluid (e.g., air or water)is permitted to move proximally past one-way seal 62, between one-wayseal 62 and surface 38.

Proximal aperture 24 may be disposed axially between one-way seal 62 andproximal seal 42. Distal aperture 26 may be disposed axially betweenthird distal seal 36 and second distal seal 34.

Cap 18 may have a stationary portion 70 and a movable portion 72.Although movable portion 72 is described herein as being separate fromvalve stem 16, it will be appreciated that movable portion 72 and valvestem 16 could be formed of a single integral piece. Stationary portion70 may remain stationary with respect to valve cylinder 39 when valve 10is inserted in valve cylinder 39. Stationary portion 70 may include aninner cylindrical member 74 and an outer cylindrical member 76. As shownin FIGS. 1A-1B, inner cylindrical member 74 and outer cylindrical member76 may be made from a single, unitary piece of material, which mayfacilitate manufacturing efficiencies. Alternatively, inner cylindricalmember 74 and outer cylindrical member 76 may be two separate piecesthat are assembled together. Outer cylindrical member 76 may include oneor more mating features 78 for mating cap 18 with an outer portion ofvalve cylinder 39. For example, mating feature 78 may be a protrusionextending radially inward and matable with a corresponding groove orindentation of valve cylinder 39. A distal surface of inner cylindricalmember 74 may rest upon a proximal outer surface of valve cylinder 39. Across-section of inner cylindrical member 74 may be “L” shaped, forminga seat, for a spring (to be described, below).

Movable portion 72 may be proximally and distally (axially) movablerelative to valve stem 16 and/or stationary portion 70. Movable portion72 may be affixed to valve stem 16, so that proximal or distal (axial)movement of movable portion 72 also causes the same motion of valve stem16. As discussed above, movable portion 72 may be integrally formed withvalve stem 16. Movable portion 72 of cap 18 may have a button shape orany other suitable shape. A rim 80 of movable portion 72 may extend in alongitudinal direction between outer cylindrical member 76 and innercylindrical member 74.

Cap 18 may be fitted with a spring 82, which may be a biasing member.Spring 82 may be a coil spring, leaf spring, or another type ofresilient member, such as any member having shape-memory properties.Spring 82 may be, for example, a compression spring. Spring 82 may beconfigured in cap 18 so that, when spring 82 is in a relaxed state,valve 10 has a first configuration relative to stationary portion 70.When movable portion 72 is moved distally so that valve 10 has a secondconfiguration, spring 82 may be in a deformed, compressed state and maystore potential energy due to the deformation (e.g., compression) ofspring 82. Spring 82 may have properties, including a stiffness, suchthat spring 82 exerts a known return force on movable portion 72 afterit has been moved distally from the first configuration to the secondconfiguration.

A cap seal 90 may be disposed between movable portion 72 and stationaryportion 70. Cap seal 90 may be, for example, an O-ring seal, a washer,or other type of structure and may be formed of elastomeric material.Alternatively, something other than a seal that provides a resistive orfrictional force between movable portion 72 and stationary portion 70may be used in place of cap seal 90. For example, instead of cap seal90, portions of movable portion 72 or stationary portion 70 may betextured or may have structures or substances disposed thereon thatincrease resistance between them. As shown in FIGS. 1A and 1B, cap seal90 may be fixed to movable portion 72, in an annular groove withinmovable portion 72, and cap seal 90 is movable with respect tostationary portion 70. Alternatively, cap seal 90 may be fixed tostationary portion 70 and movable with respect to movable portion 72.Cap seal 90 may provide a frictional force between an outer surface ofcap seal 90 and an inner surface of stationary portion 70. Thus, whenvalve 10 is in the second configuration, and spring 82 is in a deformed,compressed state, friction caused by cap seal 90 may resist a returnforce of spring 82 that urges movable portion 72 and valve stem 16proximally to the first configuration, in which spring 82 is relaxed.The relationship between a frictional force caused by cap seal 90 and areturn force caused by spring 82 may be such that valve 10 automaticallymoves from the second configuration to the first configuration in a set,predetermined amount of time. In other words, the frictional force maydelay the return of valve 10 to the first configuration. The delay mayalign with a time desired to flush an air channel of an endoscope, asdiscussed below.

A stem seal 91 may be disposed between stationary portion 70 and valvestem 16. Stem seal 91 may be, for example, an O-ring seal, a washer, orother type of structure and may be formed of elastomeric material. Asshown in FIGS. 1A and 1B, stem seal 91 may be fixed to stationaryportion 70, in an annular groove within stationary portion 70, and stemseal 91 is movable with respect to valve stem 16. Alternatively, stemseal 91 may be fixed to valve stem 16 and movable with respect tostationary portion 70. Stem seal 91 may be configured such that fluids(e.g., air or water) cannot pass proximally or distally of stem seal 91.

FIG. 1A shows valve 10 in a first configuration, in which air is flushedthrough both a water channel and an air channel of an endoscope. In thefirst configuration, spring 82 may be in a relaxed state, and movableportion 72 may be in a raised position, as a result. In the firstconfiguration, third distal seal 36 may be positioned proximal to awater inlet A of endoscope valve cylinder 39 and also distal to a wateroutlet B of endoscope valve cylinder 39. Second distal seal 34 may beproximal of water outlet B but distal to air inlet C. First distal seal32 may also be distal to air inlet C. One-way seal 62 may be proximal ofair inlet C and distal to air outlet D.

Thus, in the first configuration, water, or other fluid, from waterinlet A may not move proximally past third distal seal 36 and may thusnot move to water outlet B. Air, or other fluid, from air inlet C maynot move distally along an outer surface of valve stem 16 due to firstdistal seal 32. However, air from air inlet C may move proximally pastone-way seal 62. Air may thus pass into air outlet D and also intoproximal aperture 24. Air that has passed into proximal aperture 24 maypass distally through lumen 22 and out of distal aperture 26. Becausedistal aperture 26 is between third distal seal 36 and second distalseal 34, the air exiting distal aperture 26 may not move proximally ordistally along an outer surface of valve stem 16. However, the airexiting distal aperture 26 may exit the water outlet B. The firstconfiguration may be used after flushing an air channel of an endoscopeto ensure that water is removed from the air channel and the waterchannel before the scope is subject to further reprocessing.

FIG. 1B shows valve 10 in a second, compressed configuration, in whichwater is flushed down the air channel. Spring 82 may be compressed inthe second configuration so that movable portion 72 is translateddistally relative to the first configuration. An entirety of valve stem16 is shifted distally by a same amount by which movable portion 72 isshifted. Proximal seal 42 may remain proximal of air outlet D. One-wayseal 62 may be shifted distally relative to the first configuration, sothat air or other fluid from air inlet C may not move past one-way seal62 (e.g., fluid flow is prevented) because a distal portion of one-wayseal 62 fits in a narrowed, tapered region of endoscope valve cylinder39 so that air cannot flow proximally past the distal portion of one-wayseal 62 to reach the proximal movable flap portion of one-way seal 62.

In the second configuration, third distal seal 36 may be distal to waterinlet A, and second distal seal 34 may remain proximal of water inlet A.Therefore, water or other fluid from water inlet A may enter proximallyof third distal seal 36 but may not move proximally past second distalseal 34 along an outer surface of valve stem 16. However, water or otherfluid may enter distal aperture 26 and travel through lumen 22 andthrough proximal aperture 24. After water or other fluid exits proximalaperture 24, the water may not flow distally past one-way seal 62 orproximally past one-way seal 62. However, water or other fluid may flowout air outlet D to flush out the air channel of an endoscope.

If an operator releases movable portion 72 of cap 18 after transitioningvalve 10 from the first configuration (FIG. 1A) to the secondconfiguration (FIG. 1B), valve 10 will slowly move back to the firstconfiguration due to restorative forces exerted by spring 82. However,valve 10 may not immediately return back to the first configuration dueto frictional forces caused by cap seal 90. For example, cap seal 90 mayexert forces opposite forces exerted by spring 82, thereby delayingrelaxation of the spring 82 and return to the first configuration of thevalve 10. Valve 10 may continue to deliver water or other fluid to airoutlet D until third distal seal 36 passes proximally of water inlet A.Thus, valve 10 may deliver water or other fluid to air outlet D for apredetermined amount of time, which may be specified by a cleaningprotocol, without a user pressing on portion 72 of cap 18. For example,cap seal 90 and spring 82 may be calibrated so as to flush an airchannel for a particular, predetermined amount of time.

After a procedure using an endoscope is completed, an operator mayremove an air/water valve used during the procedure from valve cylinder39. The operator may then insert valve 10 into valve cylinder 39. Distalportion 76 cap 18 may be secured to valve cylinder 39 using matingfeature 78.

Valve 10 may be inserted into valve cylinder 39 in the firstconfiguration of valve 10. An operator may press down movable portion72, which compresses spring 82, and shifts valve stem 16 downward,relative to valve cylinder 39 and stationary portion 70. The user maythen release movable portion 72 and may attend to other aspects of apost-operative procedure. Even without operator intervention, valve 10may be maintained in the second, compressed configuration for apredetermined amount of time (e.g., thirty seconds) so as to flush waterthrough an air channel of the endoscope, thereby removing debris fromthe air channel. As discussed above, interactions between spring 82 andcap seal 90 may facilitate automatically flushing water for apredetermined amount of time. Movable portion 72 (and valve stem 16) mayeventually return to the first configuration due to a force exerted byspring 82, as discussed above. Following completion of flushing of waterthrough the air channel, valve 10 may be disposed.

Turning to FIGS. 2A and 2B, a second exemplary valve 100 may include avalve stem 116 and a cap 118 (which may be an operation portion of valve100). Valve 100 may be installed into a valve cylinder 139, which mayhave any of the properties of valve cylinder 39. Valve 100 may have anyof the properties of valve 10.

Valve stem 116 may be formed of any suitable material, including any ofthose outlined above with respect to valve stem 16 and may have any ofthe properties of valve stem 16. Valve stem 116 may include a lumen 122,which may have any of the properties of lumen 22. Lumen 122 may besubstantially formed along a central longitudinal axis of valve stem 116or along another, off-center longitudinal axis of valve stem 116.Alternatively, at least a portion of lumen 122 may be transverse to alongitudinal axis of valve stem 116. Lumen 122 may have a proximal bend124 and a distal bend 126. A midsection 128 of lumen 122 may be betweenproximal bend 124 and distal bend 126. Lumen 122 may bend up to 90degrees, approximately 90 degrees, or any other suitable amount atproximal bend 124 and/or distal bend 126. A proximal end of lumen 122may terminate at a proximal opening or aperture 130. Proximal opening130 may extend through a wall of valve stem 116 and may cause lumen 122to be in fluid connection with an area exterior to valve stem 116. Adistal end of lumen 122 may terminate at a distal opening or aperture132. Distal opening 132 may extend through a wall of valve stem 116 andmay cause lumen 122 to be in fluid connection with an area exterior tovalve stem 116. Proximal opening 130 and distal opening 132 may beradially aligned on valve stem 116. Proximal bend 124 and/or distal bend126 may be omitted. If proximal bend 124 is omitted, proximal opening130 may be in direct communication with midsection 128 of lumen 122.Similarly, if distal bend 126 is omitted, distal opening 132 may be indirect communication with midsection 128 of lumen 122. Valve stem 116may be fitted with a proximal rotation seal 140, a distal rotation seal142, and a middle rotation seal 150.

FIG. 3A shows an exemplary seal 200, the basic structure of which may beused for distal rotation seal 142. Seal 200 or features of seal 200 mayalso be used for proximal rotation seal 140 and/or middle rotation seal150. Seal 200 may be made from any appropriate material, and may beelastomeric. As shown in FIG. 3A, seal 200 may be annular and may have aroughly washer or O-ring shape. Seal 200 may have an inner opening 202defined by an inner surface 203. Surface 203 may be fit around acircumference of valve stem 116 so that inner surface 203 is in contactwith an outer surface of valve stem 116. An outer surface 204 of seal200 may contact inner surface 138 of valve cylinder 139, when valve 100is inserted into valve cylinder 139. Surfaces 203 and 204 may be flat;in other words, a wall defining opening 202 may have a substantiallyuniform thickness, except in the areas of a hole 210 and a notch 212 tobe described. Hole 210 may be formed through a wall of seal 200,extending from a surface defined by notch 212 to inner surface 203.Outer surface 204 of seal 200 may define a recessed notch 212, which maysurround hole 210. Notch 212 may have an have a substantiallyrectangular cross-section and may extend at least partially around acircumference outer surface 204, past hole 210. Notch 212 may extendcircumferentially past hole 210 in both directions (as shown) or only inone direction or the other (e.g., notch 212 may terminate near hole210). Notch 212 may have a similar width (in an axial direction) to adiameter of hole 210, or notch 212 may have a width (in an axialdirection) that is smaller than a diameter of hole 210. Notch 212 mayhave a thickness (in a radial direction) such that it extends partiallythrough a wall defining opening 202 but not entirely through the walldefining opening 202. A function of notch 212 will be discussed infurther detail below.

FIG. 3B shows an exemplary seal 300, the basic structure of which may beused for middle rotation seal 150. Seal 300 may have any of the featuresof seal 200, discussed above. Seal 300 or features of seal 300 may alsobe used for proximal rotation seal 140 and/or distal rotation seal 142.Seal 300 may be made from any appropriate material, and may beelastomeric. As shown in FIG. 3B, seal 300 may be annular and may have aroughly washer or O-ring shape. Seal 300 may have an inner opening 302defined by an inner surface 303. Surface 303 may be fit around acircumference of valve stem 116 so that inner surface 303 is in contactwith an outer surface of valve stem 116. An outer surface 304 of seal300 may contact inner surface 138 of valve cylinder 139, when valve 100is inserted into valve cylinder 139. Surfaces 303 and 304 may be flat;in other words, a wall defining opening 302 may have a substantiallyuniform thickness, except in the areas of a notch 320 to be described.Outer surface 304 of seal 300 may define a recessed notch 320, whichextend along a longitudinal length of seal 300. Notch 320 may have anhave a substantially rectangular cross-section. A function of notch 320will be discussed in further detail below. Alternatively, seal 300 maynot have a full annular shape and may instead extend around only aportion of a circumference of valve stem 116. In such a configuration,notch 320 may be omitted from seal 300.

FIGS. 3C and 3D show another exemplary seal 400, the basic structure ofwhich may be used for proximal rotation seal 140. Seal 400 may have anyof the features of seals 200, 300, discussed above. Seal 400 or featuresof seal 400 may also be used for distal rotation seal 142 and/or middlerotation seal 150. Seal 400 may be made from any appropriate material,and may be elastomeric. Seal 400 may be annular and may have a roughlywasher or O-ring shape. Seal 400 may have an inner opening 402 definedby an inner surface 403. Surface 403 may be fit around a circumferenceof valve stem 116 so that inner surface 403 is in contact with an outersurface of valve stem 116. An outer surface 404 of seal 200 may contactinner surface 138 of valve cylinder 139, when valve 100 is inserted intovalve cylinder 139. Surfaces 403 and 404 may have any of the features ofsurfaces 303, 304, discussed above. Hole 410 may be formed through awall of seal 400, extending from a surface defined by notch 412 to innersurface 403. Outer surface 404 of seal 400 may define a recessed notch412, which may surround hole 410. Hole 410 and notch 412 may have any ofthe features of hole 210 and notch 212, respectively, as discussedabove. Outer surface 404 of seal 400 may define a recessed notch 420,which extend along a longitudinal length of seal 400. Notch 420 may haveany of the properties of notch 320, discussed above. Notch 420 may bedisposed diametrically opposite of hole 410 or at another angle relativeto hole 410. Alternatively, seal 400 may not have a full annular shapeand may instead extend around only a portion of a circumference of valvestem 116. In such a configuration, notch 420 may be omitted from seal400.

As discussed above, proximal rotation seal 140, distal rotation seal142, and middle rotation seal 150 may have features of seals 200, 300,400, discussed above. Proximal rotation seal 140, distal rotation seal142, and middle rotation seal 150 may have different inner and/or outerdiameters, in order to accommodate different diameters of valve stem 116and/or valve cylinder 139 at the respective locations of proximalrotation seal 140 and distal rotation seal 142.

Proximal rotation seal 140 (which may have any of the structuresdescribed above, with respect to seal 400), may be positioned so that ahole 146 (which may have any of the properties of hole 410) of proximalrotation seal 140 aligns with proximal opening 130. A notch 147 ofproximal rotation seal 140 (which may have any of the properties ofnotch 420) may be positioned so that it is 180 degrees (diametricallyopposed) from proximal opening 130 or at a different angle relative toproximal opening 130 (as discussed below).

Distal rotation seal 142 (which may also have any of the structuresdescribed above, with respect to seal 200) may be positioned so that ahole 148 (which may have any of the properties of hole 210) of distalrotation seal 142 aligns with distal opening 132. Thus, lumen 122 may bein fluid communication with an exterior surface of proximal rotationseal 140 and distal rotation seal 142, via holes 146 and 148,respectively.

Middle rotation seal 150 (which may also have any of the structuresdescribed above, with respect to seal 300) may be positioned so that anotch 151 (which may have any of the properties of notch 320) ispositioned in line with notch 147 of proximal rotation seal 140. Middlerotation seal may be positioned 180 degrees (diametrically opposed from)proximal opening 130 and distal opening 132, or at another anglerelative to proximal opening 130 and distal opening 132 (as discussedbelow).

Proximal rotation seal 140, distal rotation seal 142, and middlerotation seal 150 may be configured so that each has a slidableinterference fit with an inner surface 138 of valve cylinder 139 whenseals 140, 142, 150 are positioned about valve stem 116. Fluids, such asair and/or water, may not move proximally or distally past distalrotation seal 142, between an outer surface of valve stem 116 and aninner surface 138 of valve cylinder 139. Fluids, such as air and/orwater, may not move proximally or distally past proximal rotation seal140 or middle rotation seal 150, between an outer surface of valve stem116 and an inner surface 138 of valve cylinder 139, except at notch 147,151, respectively.

Cap 118, which may have any of the properties of cap 18, may include astationary portion 170 and a rotatable portion 172. Although rotatableportion 172 is described herein as being separate from valve stem 116,it will be appreciated that rotatable portion 172 could be formedintegrally with valve stem 116. Stationary portion 170 may remainstationary with respect to valve cylinder 139 when valve 100 is insertedin valve cylinder 139. Stationary portion 170 may include an innercylindrical member 174 and an outer cylindrical member 176. As shown inFIGS. 2A-2B, inner cylindrical member 274 and outer cylindrical member276 may be made from a single, unitary piece of material, which mayfacilitate manufacturing efficiencies. Alternatively, inner cylindricalmember 274 and outer cylindrical member 276 may be two separate piecesthat are assembled together. Outer cylindrical member 176 may includeone or more mating features 178 for mating cap 118 with an outer portionof valve cylinder 139. For example, mating feature 178 may be aprotrusion extending radially inward that may mate with a correspondinggroove or indentation of valve cylinder 139. A distal surface of innercylindrical member 174 may rest upon a proximal outer surface of valvecylinder 139. A cross-section of inner cylindrical member 174 may be “L”shaped, forming a radially-outward directed flange, or seat, for aspring (to be described).

Rotatable portion 172 may be rotatable relative to valve cylinder 139and/or stationary portion 170. Although rotatable portion 172 isdescribed separately from valve stem 116, it will be understood thatrotatable portion 172 and valve stem 116 could be formed of a single,integral structure. Rotatable portion 172 may be affixed to valve stem116, so that rotation of rotatable portion 172 also causes rotation ofvalve stem 116. Rotatable portion 172 of cap 118 may have a buttonshape, a knob shape, or any other suitable shape. An exterior surface ofrotatable portion 172 may have gripping surfaces to assist a user ingripping onto rotatable portion 172. A rim 180 of rotatable portion 172may extend in a longitudinal direction between outer cylindrical member176 and inner cylindrical member 174. Rotatable portion 172 may also beproximally and distally movable. Rotatable portion 172 may rotate whileit is being translated proximally or distally. For example, a user couldpress down on rotatable portion 172, which could engage a ramp or othersurface and cause rotatable portion 172 to rotate as it translatesproximally or distally.

Cap 118 may be fitted with a spring 182, which may be a biasing member.Spring 182 may be a coil spring, leaf spring, or another type ofresilient member, such as any member having shape-memory properties.Spring 182 may be, for example, a torsion spring. Alternatively, spring182 may be a compression spring. Spring 182 may be configured in cap 118so that, when spring 182 is in a relaxed state, valve 100 has a firstconfiguration. When rotatable portion 172 is rotated (e.g., in aclockwise or counterclockwise direction) about a longitudinal axis ofthe valve, so that valve 100 has a second configuration, spring 182 maybe in a deformed state and may store potential energy due to thedeformation of spring 182. Spring 182 may have properties, including astiffness, such that spring 182 exerts a known return force on rotatableportion 172, after it has been rotated from the first configuration tothe second configuration.

A cap seal 190 may be disposed between rotatable portion 172 andstationary portion 170. Cap seal 190 may have any of the properties ofcap seal 90. Alternatively, something other than a seal that provides aresistive or frictional force between movable portion 172 and stationaryportion 170 may be used in place of cap seal 190. For example, insteadof cap seal 190, portions of movable portion 172 or stationary portion170 may be textured or may have structures or substances disposedthereon that increase resistance between them. Cap seal 190 may be, forexample, an O-ring seal, a washer, or other shape and may be formed ofelastomeric material. As shown in FIGS. 2A and 2B, cap seal 190 may befixed with respect to rotatable portion 172 in an annular groove withinrotatable portion 172, and cap seal 190 may be rotatable with respect tostationary portion 170. Alternatively, cap seal 190 may be fixed withrespect to stationary portion 170 and rotatable with respect torotatable portion 172. Cap seal 190 may provide a frictional forcebetween an outer surface of cap seal 190 and an inner surface ofstationary portion 170. Thus, when valve 100 is in the secondconfiguration, and spring 182 is in a deformed state, friction caused bycap seal 190 may resist a return force of spring 182 that urges valve100 to the first configuration, in which spring 182 is relaxed. Therelationship between a frictional force caused by cap seal 190 and areturn force caused by spring 182 may be such that valve 100automatically moves from the second configuration to the firstconfiguration in a set, predetermined amount of time. In other words,the frictional force may delay the return of valve 100 to the firstconfiguration. The delay may align with a time desired to flush an airchannel of an endoscope, as discussed below.

A stem seal 191 may be disposed between valve stem 116 and inner surface138 of valve cylinder 139. Stem seal 191 may be, for example, an O-ringseal, a washer, or other type of structure and may be formed ofelastomeric material. Stem seal 191 may be fixed to valve stem 116. Stemseal 191 may be configured such that fluids (e.g., air or water) cannotpass proximally or distally of stem seal 191.

FIG. 2A shows valve 100 positioned in valve cylinder 139 and in thefirst configuration described above. Spring 182 is in a relaxed, neutralstate so that spring 182 does not exert a force to rotate rotatableportion 172 and valve stem 116.

Proximal rotation seal 140 may be positioned so that hole 146 axiallyaligns with air outlet D but is angularly offset (relative to alongitudinal axis) from air outlet D. For example, hole 146 may beoffset by 180 degrees or another angle (e.g., 90 degrees or 45 degrees)from air outlet D. FIG. 2A shows hole 146 as being offset from airoutlet D by 180 degrees. Similarly, distal rotation seal 142 may bepositioned so that hole 148 axially aligns with water inlet A but isangularly offset (relative to a longitudinal axis) from water inlet A.For example, hole 148 may be offset by 180 degrees or another angle(e.g., 90 degrees or 45 degrees) from water inlet A. FIG. 2A shows hole148 as being offset from water inlet A by 180 degrees. Holes 146 and 148may be offset from air outlet D and water inlet A, respectively, by thesame angle (e.g., 180 degrees).

Proximal rotation seal 140 may further be positioned so that notch 147is axially and radially aligned with air outlet D. Middle rotation seal150 may also be positioned so that notch 151 is axially and radiallyaligned with air inlet C.

In the first configuration, water or other fluid from water inlet A maynot pass proximally past distal rotation seal 142. Thus, water or otherfluid may not exit either water outlet B or air outlet D. Air or otherfluid from inlet C may pass proximally and distally past middle rotationseal 150 because notch 151 is aligned with air inlet C. Thus, air orother fluid may move distally and exit through water outlet B. Air orother fluid may also pass proximally past proximal rotation seal 140because notch 147 is aligned with air outlet D. Thus, in the firstconfiguration, air or other fluid passes from air inlet C through bothwater outlet B and air outlet D. The first configuration may be usedafter flushing an air channel of an endoscope to ensure that water isremoved from the air channel and the water channel before the scope issubject to further reprocessing.

FIG. 2B shows valve 100 in the second configuration, discussed above. Totransition valve 100 from the first configuration to the secondconfiguration, a user may rotate rotatable portion 172 of cap 118. Forexample, as shown in FIGS. 2A-2B, rotatable portion 172 may be rotatedby 180 degrees to transition valve 100 from the first configuration tothe second configuration. Alternatively, rotatable portion 172 may berotated by another amount, which may be equivalent to an offset of holes146, 148 in the first configuration. In the second configuration, hole146 of proximal rotation seal 140 may be axially and radially(angularly) aligned with air outlet D, and notch 147 may not be alignedwith air outlet D. Similarly, hole 148 of distal rotation seal 142 maybe axially and radially aligned with water inlet A. Middle rotation seal150 may be rotated so that notch 151 no longer aligns with air inlet C.

In the second configuration, water or other fluid from water inlet A maypass through hole 148 and through distal opening 132 and into lumen 122.Water or other fluid may travel proximally through lumen 122, throughproximal opening 130, through hole 146, and into air outlet D. Water orother fluid from water inlet A may not pass proximally past distalrotation seal 142. Water or other fluid exiting hole 146 may not passdistally past proximal rotation seal 140. Air or other fluid from airinlet C may not pass distally past middle rotation seal 150 becausenotch 151 is not aligned with air inlet C. Thus, in the secondconfiguration, only water or other fluid may exit only through airoutlet D to be flushed through an air channel of an endoscope and clearthe air channel of debris following a procedure.

In the second configuration, if a user is not operating cap 118 of valve100, valve 100 may remain for a time in the second configuration due toan interaction between the spring 182 and the cap seal 190. Over aperiod of time (e.g., a predetermined period of time), a restorativeforce of spring 182 may return valve 100 to the first configuration. Forexample, cap seal 190 may exert forces opposite forces exerted by spring182, thereby delaying relaxation of the spring 182 and return to thefirst configuration of the valve 100. Valve 100 may progressively bereturned to the first configuration (e.g., it may slowly move from thesecond configuration to the first configuration). Because the proximalrotation seal 140 and the distal rotation seal 142 may each have arecessed notch (such as notch 212) adjacent to holes 146 and 148,respectively, water or other fluid may continue to flow through holes146 and 148 even after hole 146 is no longer directly aligned with airoutlet D and hole 148 is no longer directly aligned with water inlet A.For example, the notches may extend around a portion of a circumferenceof proximal rotation seal 140 and/or distal rotation seal 142 so that,as rotation seal 140 or 142 rotates along with valve stem 116, the notchmay continue to be adjacent to air outlet D or water inlet A. Water orother fluid may flow from water inlet A, into the notch of distalrotation seal 142, into hole 146, through distal opening 132, throughlumen 122, through proximal opening 130, out of hole 148, through thenotch of proximal rotation seal 140, and into water outlet D. Water orother fluid may cease to flow when the notches of proximal rotation seal140 and/or distal rotation seal 142 are no longer in communication withair outlet D and/or water inlet A, respectively. Thus, valve 100 maydeliver water to air outlet D for a predetermined amount of time, whichmay be specified by a cleaning protocol. For example, cap seal 190 andspring 182 may be calibrated so as to flush an air channel for aparticular, predetermined amount of time

An exemplary method for using valve 100 is provided herein. Following aprocedure with an endoscope, the endoscope may be removed from apatient. In order to prepare the endoscope for reprocessing, anair/water valve may be removed from valve cylinder 139. Valve 100 maythen be inserted into valve cylinder 139 while valve 100 is in the firstconfiguration. In the first configuration, as discussed above, neitherair nor water may be flushed through any channel of the endoscope. Auser may rotate rotatable portion 172 of cap 118 to transition valve 100to the second configuration. The user may then release rotatable portion172 of cap 118 and may attend to other aspects of a post-operativeprocedure. Even after rotatable portion 172 is released, water or otherfluid may continue to flow for a predetermined time from water inlet Aand out of air outlet D, through the air channel of the endoscope. Aftervalve 100 has flushed water or other fluid through the air channel forthe predetermined amount of time, the valve 100 may be removed fromvalve cylinder 139 and may optionally be disposed.

While principles of the present disclosure are described herein withreference to illustrative examples for particular applications, itshould be understood that the disclosure is not limited thereto. Thosehaving ordinary skill in the art and access to the teachings providedherein will recognize additional modifications, applications, andsubstitution of equivalents all fall within the scope of the examplesdescribed herein. Accordingly, the invention is not to be considered aslimited by the foregoing description.

1-20. (canceled)
 21. A medical valve comprising: a valve stem; and anoperation portion, including: a stationary portion; and a movableportion, wherein the movable portion is movable relative to thestationary portion and fixed relative to the valve stem; wherein, in afirst configuration of the medical valve, a first fluid flows into themedical valve via a second inlet of a valve cylinder and out of themedical valve via a first outlet of the valve cylinder and a secondoutlet of the valve cylinder; and wherein in a second configuration, asecond fluid flows into the medical valve via a first inlet of the valvecylinder and out of the medical valve via the second outlet of the valvecylinder.
 22. The medical valve of claim 21, wherein the first fluid isair, and wherein the second fluid is liquid.
 23. The medical valve ofclaim 21, wherein, in the second configuration, the second fluid flowsout of the medical valve only via the second outlet of the valvecylinder.
 24. The medical valve of claim 21, wherein the valve stemincludes a lumen having a proximal opening and a distal opening,wherein, in the first configuration, (a) the proximal opening isrotationally offset from the second outlet and (b) the distal opening isrotationally offset from the first inlet, and wherein, in the secondconfiguration, (a) the proximal opening is aligned with the secondoutlet and (b) the distal opening is aligned with the first inlet in thesecond configuration.
 25. The medical valve of claim 24, wherein a firstseal is axially aligned with the first inlet and the distal opening ofthe lumen, wherein the first seal includes a first hole formed through awall of the first seal, wherein the first hole is aligned with thedistal opening of the lumen; and wherein, in the second configuration,the first hole is aligned with the first inlet.
 26. The medical valve ofclaim 25, wherein a second seal is axially aligned with the secondinlet, wherein the second seal includes a notch, wherein the notchextends along a longitudinal length of the second seal, wherein, in thefirst configuration, the notch is aligned with the second inlet, andwherein, in the second configuration, the notch is rotationally offsetfrom the second inlet.
 27. The medical valve of claim 26, wherein athird seal is axially aligned with the second outlet and the proximalopening of the lumen, wherein the third seal includes a second holeformed through a wall of the third seal, wherein the second hole isaligned with the proximal opening of the lumen, and wherein, in thesecond configuration, the second hole is aligned with the second outletin the second configuration.
 28. The medical valve of claim 21, whereinrotation of the valve stem about a longitudinal axis of the valve stemtransitions the medical valve from the first configuration to the secondconfiguration.
 29. The medical valve of claim 21, wherein the operationportion further includes a biasing member disposed between thestationary portion and the movable portion.
 30. The medical valve ofclaim 29, wherein moving the movable portion in a first directionrelative to the stationary portion deforms the biasing member, whereinthe deformed biasing member exerts a restorative force against themovable portion, wherein a relationship between a frictional forcebetween a seal and one of the stationary portion and the movable portionresists a movement of the movable portion in a second direction and therestorative force is such that, after the movable portion is movedrelative to the stationary portion, the movable portion willautomatically return to the first configuration after an amount of time.31. A medical valve comprising: a valve stem; a first seal disposed onthe valve stem; a second seal disposed on the valve stem; a third sealdisposed on the valve stem; and a movable portion fixed to the valvestem and configured to be movable relative to a valve cylinder, whereinthe medical valve is configured to be inserted into the valve cylindersuch that a water inlet of the valve cylinder is axially aligned withthe first seal, an air inlet of the valve cylinder is axially alignedwith the second seal, and an air outlet of the valve cylinder is axiallyaligned with the third seal, wherein, in a first configuration of themedical valve, a first fluid flows into the medical valve via the airinlet and out of the medical valve via the air outlet and a water outletof the valve cylinder; and wherein, in a second configuration of themedical valve, a second fluid flows into the medical valve via the waterinlet and out of the medical valve via the air outlet.
 32. The medicalvalve of claim 31, wherein rotation of the valve stem about alongitudinal axis of the valve stem transitions the medical valve fromthe first configuration to the second configuration.
 33. The medicalvalve of claim 31, wherein the first seal includes a first recessednotch extending partially around an outer circumference of the firstseal and a first hole within the first recessed notch of the first seal,wherein, in the first configuration, the first hole is rotationallyoffset from the water inlet, wherein, in the second configuration, thefirst hole is aligned with the water inlet, wherein the third sealincludes a second recessed notch extending partially around an outercircumference of the third seal and a second hole within the secondrecessed notch, wherein, in the first configuration, the second hole isrotationally offset from the air outlet, and wherein, in the secondconfiguration, the second hole is aligned with the air outlet.
 34. Themedical valve of claim 33, wherein the valve stem includes a lumenhaving a proximal opening and a distal opening, wherein, in the firstconfiguration, the proximal opening is rotationally offset from the airoutlet and the distal opening is rotationally offset from the waterinlet, wherein, in the second configuration, the proximal opening isaligned with the air outlet and the distal opening is aligned with thewater inlet, wherein the first hole of the first seal is aligned withthe distal opening of the lumen, and wherein the second hole of thethird seal is aligned with the proximal opening of the lumen.
 35. Themedical valve of claim 31, wherein the second seal includes a thirdrecessed notch extending along a longitudinal length of the third seal,wherein, in the first configuration, the third recessed notch is alignedwith the air inlet, and wherein, in the second configuration, the thirdrecessed notch is rotationally offset from the air inlet.
 36. Themedical valve of claim 31, wherein, in the second configuration, thesecond fluid flows out of the medical valve via only the air outlet. 37.The medical valve of claim 31, wherein the medical valve furtherincludes a biasing member and a stationary portion, wherein the biasingmember is disposed between the stationary portion and the movableportion, wherein moving the movable portion in a first directionrelative to the stationary portion deforms the biasing member, whereinthe deformed biasing member exerts a restorative force against themovable portion, wherein a relationship between a frictional forcebetween a seal and one of the stationary portion and the movable portionresists a movement of the movable portion in a second direction and therestorative force is such that, after the movable portion is movedrelative to the stationary portion, the movable portion willautomatically return to the first configuration after an amount of time.38. A medical valve comprising: a valve stem defining a longitudinalaxis, wherein the valve stem is configured to be received within a valvecylinder having a first inlet, a first outlet, a second inlet, and asecond outlet; a first seal disposed on the valve stem, wherein thefirst seal is configured to be axially aligned with the first inlet; anda second seal disposed on the valve stem, wherein the second seal isconfigured to be axially aligned with the second outlet; wherein themedical valve is configured to be rotated about the longitudinal axisbetween (a) a first configuration, in which a first fluid flows into themedical valve via only the second inlet of a valve cylinder and out ofthe medical valve via the first outlet of the valve cylinder and (b) asecond configuration, in which a second fluid flows into the medicalvalve via a only the first inlet of the valve cylinder and out of themedical valve via the second outlet of the valve cylinder.
 39. Themedical valve of claim 38, wherein the first seal includes a first holeformed through a wal of the first seal, wherein the second seal includesa second hole formed through a wall of the second seal, wherein, in thefirst configuration, the first hole and the second hole each face afirst direction, wherein, in the second configuration, the first holeand the second hole each face a second direction, and wherein the firstdirection differs from the second direction.
 40. The medical valve ofclaim 39, wherein the valve stem defines a lumen that terminates in adistal opening and in a proximal opening, wherein the first hole of thefirst seal is aligned with the distal opening of the lumen, and whereinthe second hole of the second seal is aligned with the proximal openingof the lumen.